Return current drier



April 12, 1932. A. w. LlssAER ETAL RETURN CURRENT DRIER Filed May 14, ]930 vwwntoi C? @atome/1g TVR COMP-j bly-nk A Patented Apr. 12, 1932 uNirE-D..sma dem ADoLrii W. LissAnnR .AND JAMESJR. ooFnEY, or ,LoUrsvILLE,. KENTUCKY, n.Ass'isrivcns To LouisviLLE. DRYING vivrnciizuxrnny co., onmomsvnnnfKENTUCKE i nnfrulaivcnfi'truilv'ry unina f Appiieationmed M'y 14, 51930.# serial No-452.5105

more Aparticularly to the type of drier/Where# inlthe feed end is subjectexteriorlyftoz the- I direct action of the furnace combustion gases toprevent sticking of vvetmaterialfed intoi the'i drier. i

The furnace gases: abouti the feed endl of the drier' are conveyed Vtovvithin-the dis licharge end of the drier through a serieswofl-f' U-shaped conduits formingrhollow flights, secured tomthe innerlateralsurface of the drier and from Where the furnace gases are drawn to and through the feed end by a fan.

An object of the invention is to provide a drier of the type referred to, Which presents a large axially unobstructed space, through Which the material to be dried is tumbled as the drier rotates.

Another object of the invention is to provide a drier of the type referred to, in which the flights for the material at the inner periphery of the shell of the drier are heated `by the hotter gases.

255" Another object of the invention is to provide a drier of the type referred to, in which the hollow or channelled flights are of such cross-sectional area that keying or anchoring of material to be dried betvveenthe iights and the shell is reduced to a minimum.

In the appended drawings forming part of this application, Figure 1 is a longitudinal section through a drier embodying our invention.

;' i Figure 2 is a cross-section on line 2-2,

Figure 1.

Figure Figure 1. Figure 4 is a fragmentary longitudinal 40" section through a conduit on line 4-4, Figure 2 and Figure 5 is a cross-section through the conduit on line 5 5, Figure 4.

, Referring to the draWings,'7 is the shell of l5-*the drier mounted to revolve, the driving and bearing mechanisms for same being only shown in dotted lines. The stationary feeding end 8 of the drier carries the feeding n trough 9 through which material to be dried mus supplied.

3 is a similar section on line 3-3, Y

Tiiypruon QfftheaShuiauf@ feediafgw endx-is surroundedffby'a chamber 10', ini Toomdrierg rsimilariiseals are falso: provi ded 'between 5:

tthe shell and thefeed end 8. Theiportionoff bers 17 which overlap the plate 14: of the conduit. It is therefore apparent that although the structural members 17 limit lateral and radial movement of the conduits 13, they permit free longitudinal movement to said conduits 13 within the shellf?, although said conduits are locked to the shell at the hot gases inlets. The structural members 17V which retain the conduit 13 against the shellV 7 alsoV prevent the clogging of the material to be'dried between the shell and the conduits.

By forming the conduits 13 of U-shaped cross section with the curved part directed inwardly, we provide a series of hollow heated flights for the material to be dried, which facilitate the liow of material to be dried through the drier and prevent the keying of the material as it travels through the drier. To better stir the material during its travel in the drier, the convex parts of the conduits are provided with baffles or additional flights 19, see Figure 3.

In view of the fact that the interior of the shell 'l' is substantially unobstructed, the material during its travel Vfrom the feed end to the discharge end, is constantly subject to the radiant heat generated by the hollow flights or conduits 13, in addition to being subject to the return hot gases drawn through the conduits 13 by the fan 16. The absence of a central conduit in this type of drier permits the tossing of the material to be dried through the entire width of the shell.

From the above description and drawings, it will be seen that our return current drier provides a centrally unobstructed drier with a series of hollow heated flights in form of conduits, U-shaped in cross-section, secured firmly within the inner lateral surface of the drier, so that the said conduits or hollow liights, although prevented from lateral and radial movement, are free to move longitudinally. We claim:

1. In a return current drier, a shell, a plurality of conduits, U-shaped in cross-section, disposed on the interior periphery of the shell, means securing said conduits to the lateral surface of the shell to prevent their lateral and radial movement, and rolling means interposed between the conduit and the securing means to permit a longitudinal displacement of said .conduits relative to the shell, said conduits establishing communication between the exterior lateral surface of the shell and the interior thereof, at substantially opposite ends of said shell.

2. In a return current drier, a shell, a plurality of conduits U-shaped in cross-section, disposed on the interior periphery, of the shell, structural members securing said conduits to the lateral surface of the shell, to prevent their lateral and radial movement relative to the shell, and means interposed be- Y tween the structural members and the conduits at suitable intervals to permit said conduits to move longitudinally in said structural members, said conduits being anchored to said inner periphery of the shell at one end thereof.

3. In a return current drier, a shell, a plurality of conduits U-shaped in cross-section, each of said conduit-s having a closed end and an open end, a plate covering the open part of the U-conduits substantially through its entire length, except near the closed end to provide an opening into the conduit, structural members carried on the interior of the shell for engaging the conduits in proximity of the plate to prevent` the conduits from lateral and radial movement within the shell, said shell having openings at thelateral surface thereof, registering with the opening in the conduit at the closed end, and whereat said conduit is anchored tothe shell, and bal-ls interposed between said structural members Yand conduit at suitable intervals to permit said conduit to move longitudinally in the shell.

ADOLPH W. LISSAUER. JAMES R. COFFEY. 

